I. Field of the Invention
This invention relates to the construction of multistory buildings employing prefabricated panels and modules, and more particularly with a method of construction in which, after the panels and modules are erected on the job site, concrete is poured to create a structural framework of beams and columns.
II. Description of the Related Art
Multistory, noncombustible, building construction typically is of one of five basic structural types or combinations thereof: reinforced concrete frame, reinforced wall bearing masonry, structural steel framework, precast concrete framework, or light gage steel bearing wall. Each of these methods of construction is subject to cost disadvantages due to one or more of: time, labor, materials, weight, and complexity of assembly. Reinforced concrete frame construction requires the on site labor and time to build forms for the wet concrete, waiting for it to harden, and then time and labor to remove the used forms. Thereupon, the building is completed and finished on site with expensive job site labor and materials. Reinforced wall bearing masonry uses concrete block walls held together with mortar, then reinforced with steel rods and filled with concrete to produce the bearing walls. This is reasonably economic in materials and time, but is limited to a few stories high and then must be completed with job site materials and labor, at prime cost. Structural steel or precast concrete framework construction is commonly used in highrise work, but require the heavy steel or concrete supporting frame structure; the ceilings, walls and all the interiors to be completed and finished with on site labor and materials, a costly construction.
Light gage steel bearing wall construction employs framing partitions of light gage steel members assembled into panels. These members are load bearing and can be assembled into panels at the job site, prior to erection, but can be assembled more economically in a controlled factory environment. However, the remainder of the building then is completed and finished with costly job site labor and materials.
To some extent, the just discussed methods of multistory building can benefit economically from the use of a combination of prefabricated wall panels and modules, the modules often including bathrooms and kitchens. Such panels and modules are not load bearing and are put in place after the load bearing columns and beams of concrete or steel are built and the floors laid.
An early patent for reinforced concrete construction issued to Thomas Edison in 1917, U.S. Pat. No. 1,219,272. Frederick 4,136,495; Koizumi, et.al. 4,211,045; Wilnau 4,409,764 and Luedtke 5,048,257 combine the advantages of reinforced concrete and steel framework by using portions of the steel framework as non-removable forms for the poured concrete columns and beams.
Oboler 4,625,484 employs non-load bearing, light weight floor and wall panels, along with I-beams, etc., to enable concrete to be poured around the panels to form a concrete shell.
Grutsch 4,516,372 uses foam plastic wall panels, positioned spaced apart for concrete to be poured therebetween to form reinforced concrete walls.
Sikes 3,698,147 assembles on site hollow metal columns, each having several parts; then erects the columns on the foundation. Outer and inner wall panels are attached to the columns; lastly, the columns are filled with concrete. The inner and outer wall panels can be fabricated off site and then on site be connected to the erected columns, prior to pouring the concrete.
Spillman 3,683,577 casts in place concrete columns and beams, using wall panels as physical shuttering forms, but the wall panels have no actual contact with the concrete.
Piazzalunga 4,078,345 prefabricates entire room units, including kitchens and bathrooms; the walls, ceiling and floor are of reinforced concrete. The entire room unit is dropped into place on a foundation having imbedded vertical steel beams, which are covered with concrete and define the perimeter of each room. The room units then are coupled to the vertical beams.
Berger 3,751,864 teaches the prefabrication of modular units, each of which can encompass one or more rooms, and includes pre-installation of electrical and plumbing needs. The walls surrounding each unit and its ceiling are of corrugated steel. During erection of the building, the modules are positioned next to each other, with spaces therebetween, and vertical form boards are inserted into those spaces to complete, with adjacent corrugations, vertical forms for columns, to be filled with poured concrete. Similarly, horizontal form boards are secured below the tops of the corrugated walls of two adjacently spaced modules and define therewith a horizontal form, which is filled with concrete to make a ceiling beam.
McWethy 4,525,975 prefabricates modules, such as hotel rooms, each having a reinforced concrete floor, nonloadbearing walls, plumbing and electrical lines. The modules of one level are placed adjacent to each other, with vertical space between their walls. These adjacent walls then are latched to each other for maintaining the vertical space. Thereupon, concrete is poured into the vertical space to make an entire concrete wall surrounding these sides of the module. After the concrete is hardened to become load bearing, the next level of modules is put in place, with the reinforced concrete floor becoming the ceiling of the lower level module.
Swerdlow 4,338,759 prefabricates wall panels, each having a plurality of load bearing steel studs and a plurality of vertical tubes disposed on sixteen inch centers. In the top of each wall module is a U-shaped channel which is in fluid communication with the open tops of the vertical tubes. After the panels for one or more rooms are set up on a single floor level and are interconnected, a precast concrete ceiling is placed on top of the panels. The studs in the panels support the compression load of the ceiling. Thereupon, in a single pour, the channels and tubes are filled with concrete, and become load bearing columns and beams, respectively, all lying within the wall panels.
Mouglin 3,678,638 fabricates room modules off site and then trucks them to the job site. Hence, the room modules are limited to tractor trailer width of ten to twelve feet. The wall and ceiling panels of a room module include a complex arrangement of steel U and L-channels, which are welded together to create a reinforcing framework for each panel and to define portions of open faced forms, T-shaped for beams and rectangular for columns. At the job site, room modules for one level are positioned next to, but slightly spaced from each other, with the open channels facing each other to complete most of the form portions. The spaces between modules then are bridged by additional form members; after which the concrete is poured, to fill the beam and column forms. After the concrete is sufficiently hardened to be stress loadbearing, the next level of room modules are set into place.
The above presented prior art, which is a minute sampling of the vast amount of art, clearly shows a recognition of the advantages of prefabricated, preferably factory produced under controlled environment, wall panels, room units and modules. Unfortunately, the specific prior art solutions have been, to a great extent, impractical and therefor not utilized. For example, the prior art teachings require one or more of: units and modules too large and/or too heavy to be transported from factory to building site; too many different component parts needed to be in factory inventory and then be design-selected at the factory and job site for a specific part of a building, such design-selection being by experienced and costly labor; the use of unique forms within the panels and modules for receiving concrete for making therein columns and beams; the need for on site pouring of large quantities of concrete to form complete shells around the prefabricated room units, thus resulting in great compression force to the walls and supports on the lower levels, as well as long hardening and curing times.